Switch control structures are widely used in machinery and equipment; the current switch control mode on the market mainly relies on electromagnetic force switches or mechanical switches to achieve the on-off control of liquid circuits, gas circuits and electric circuits, etc. The direct point-to-point control mode can realize effective and short-time control of switches to be controlled. For example, machine power switches or pipe valve switches and so on can use mechanical switches to realize manual control or use electromagnetic switches to achieve automatic control of electric circuits.
Mechanical switches in sophisticated equipment are unable to achieve linkage control of each switch by manual operation, and if solenoid valves are used to control each switch, for one thing, there are too many valves, signal input channels and signal output channels arranged on a control panel and used for controlling valves correspondingly increase so that the linkage effect among switches becomes unreliable; for another, too many solenoid valves increase the cost of switch elements and the cost of circuit control. Therefore, in case of higher requirements for linkage, several above-mentioned switch control structures are unable to provide a stable linkage guarantee in addition to relatively high cost.
A document (Publication Number: CN 201594476 U) discloses a new-type cam switch, comprising a switch base, a cam, slide bars and electrical contact springs; the cam, comprising an upper cam and a lower cam, is arranged on the switch base via a camshaft; the eccentric angle difference between the upper cam and the lower cam is 15-45 degrees, both sides of the cam are provided with slide bars which are in active link to the switch base, up-down staggered and in touch with the cam via tops; the electrical contact springs are classified into static contact springs and movable contact springs, the slide bars are provided with movable contact springs, static contact springs are arranged on the switch base corresponding to movable contact springs, and a return mechanism is arranged between the slide bars and the switch base. The new-type cam switch is simple in structure, and both the slide bars are flexible in motion. However, the new-type cam switch cannot be used for more switch control structures, in particular to precise medical equipment with many switches, and is unable to conduct accurate linkage control of switches.
With the development of technology, control of switches in precise medical equipment is increasingly demanding. For example, medical equipment (such as blood gas analyzers, blood analyzers and biochemical analyzers, etc.) has linkage control of liquid circuits, gas circuits and electric circuits, etc. Under the circumstances, the switch control sequence linkage shall be more precise; in addition, the cost of switches shall be subject to strict control as more switches are in use.